Chrome's "touch to search" option has been floating around ever since beta version 38, but it's finally hit the stable channel for good and received an official announcement with Chrome 43, which is rolling out to users as you read this post. The feature allows users to search for highlighted text automatically.

UPDATE: 2015/06/03 8:17pm PDT BY

A previous version of this post showed screenshots not related to the new touch-to-search functionality. New screenshots have been added above.

Besides touch to search, the update is supposed to improve performance and squash some bugs, and allow users to check out faster by automatically filling in Google Wallet information to checkout forms for signed-in users.

You can wait for the update to hit your device, or just grab it from APK Mirror.

Source: Chrome Releases Blog